Maintenance, repair and operations is fixing any sort of mechanical or electrical device should it become out of order or broken (known as repair or unscheduled maintenance) as well as performing the routine actions which keep the device in working order (known as scheduled maintenance) or prevent trouble from arising (preventive maintenance). MRO may be defined as, "All actions which have the objective of retaining or restoring an item in or to a state in which it can perform its required function. The actions include the combination of all technical and corresponding administrative, managerial, and supervision actions."